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Crosses in the sky. The planes seem to play making crosses in the Vistabella sky. And a beautiful sun is a participant in this game. How nice to be able to observe! And to be able to share it in the Photos of La Vanguardia Readers.
Airplanes form a vapor trail after the kerosene combustion process. The gases expelled by the engine come out at a much higher temperature than the outside temperature.
The sharp contrast in temperatures at a height greater than 30,000 feet (-50 degrees in the atmosphere) causes the immediate condensation of the water present in this mixture of substances.
This causes us to see these kinds of elongated ice clouds that dissipate after a few seconds and that if they cross, they create attractive geometric shapes, like these crosses in the photographs.
This phenomenon is known in the Anglo-Saxon and aeronautical world as contrail - a word that comes from the fusion of the words condensation (trail) or in Spanish, condensation trail.
